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法律研究如何在 MySQL 中檢索一行隨機行或多行隨機行？
你可以使用 RAND() 方法來實現。要檢索一行隨機行，請使用以下語法
SELECT *FROM yourTableName ORDER BY RAND() LIMIT yourIntegerNumber;
為了瞭解上面的語法，讓我們建立一個表。建立表的查詢如下
mysql> create table gettingRandomRow -> ( -> CustomerId int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> CustomerName varchar(100) -> ); Query OK, 0 rows affected (0.45 sec)
使用插入命令在表中插入一些記錄。查詢如下 −
mysql> insert into gettingRandomRow(CustomerName) values('Chris');
Query OK, 1 row affected (0.14 sec)
mysql> insert into gettingRandomRow(CustomerName) values('Robert');
Query OK, 1 row affected (0.10 sec)
mysql> insert into gettingRandomRow(CustomerName) values('Ramit');
Query OK, 1 row affected (0.15 sec)
mysql> insert into gettingRandomRow(CustomerName) values('James');
Query OK, 1 row affected (0.11 sec)
mysql> insert into gettingRandomRow(CustomerName) values('Jace');
Query OK, 1 row affected (0.12 sec)
mysql> insert into gettingRandomRow(CustomerName) values('Mike');
Query OK, 1 row affected (0.15 sec)
mysql> insert into gettingRandomRow(CustomerName) values('Sam');
Query OK, 1 row affected (0.17 sec)
mysql> insert into gettingRandomRow(CustomerName) values('Bob');
Query OK, 1 row affected (0.12 sec)
mysql> insert into gettingRandomRow(CustomerName) values('Carol');
Query OK, 1 row affected (0.11 sec)
mysql> insert into gettingRandomRow(CustomerName) values('David');
Query OK, 1 row affected (0.16 sec)
mysql> insert into gettingRandomRow(CustomerName) values('Maxwell');
Query OK, 1 row affected (0.14 sec)
mysql> insert into gettingRandomRow(CustomerName) values('Larry');
Query OK, 1 row affected (0.13 sec)
mysql> insert into gettingRandomRow(CustomerName) values('John');
Query OK, 1 row affected (0.11 sec)使用 select 語句顯示錶中的所有記錄。查詢如下 −
mysql> select *from gettingRandomRow;
以下是執行結果
+------------+--------------+ | CustomerId | CustomerName | +------------+--------------+ | 1 | Chris | | 2 | Robert | | 3 | Ramit | | 4 | James | | 5 | Jace | | 6 | Mike | | 7 | Sam | | 8 | Bob | | 9 | Carol | | 10 | David | | 11 | Maxwell | | 12 | Larry | | 13 | John | +------------+--------------+ 13 rows in set (0.00 sec)
以下是獲取一行隨機行或多行隨機行的查詢。
情況 1：查詢如下 −
mysql> select *from gettingRandomRow order by rand() LIMIT 1;
以下是執行結果
+------------+--------------+ | CustomerId | CustomerName | +------------+--------------+ | 13 | John | +------------+--------------+ 1 row in set (0.00 sec)
情況 2：查詢如下 −
mysql> select *from gettingRandomRow order by rand() LIMIT 2;
以下是執行結果
+------------+--------------+ | CustomerId | CustomerName | +------------+--------------+ | 2 | Robert | | 3 | Ramit | +------------+--------------+ 2 rows in set (0.00 sec)
情況 3：查詢如下 −
mysql> select *from gettingRandomRow order by rand() LIMIT 2;
以下是執行結果
+------------+--------------+ | CustomerId | CustomerName | +------------+--------------+ | 4 | James | | 9 | Carol | +------------+--------------+ 2 rows in set (0.00 sec)
更新時間： 30-Jul-2019
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